The invention is directed to tooling for machining operations and, more particularly, directed to a toolholder and an apparatus for holding the toolholder secure within a tool support member during machining operations.
Minimizing the downtime of a machine tool in a production environment is critical to the success of a manufacturing facility. Historically, one major contributor to such downtime was the time needed to change damaged or worn out cutting tools used by the machine tool. A cutting tool is held by a toolholder, which is typically mounted within a tool support member secured to a machine tool. When the cutting tool must be replaced, the entire toolholder with the cutting tool is removed from the spindle. A number of commercial couplings permit quick connecting and disconnecting of the toolholder to and from the spindle to expedite the tool changing process. One such device is described in U.S. Pat. No. 4,736,659 entitled xe2x80x9cApparatus for Holding a Toolholder Shank.xe2x80x9d This patent is co-owned by the Assignee of the present application and is hereby incorporated by reference. The apparatus described in that patent utilizes two locking balls which are urged radially outwardly within a tool support member to engage apertures on the shank of a toolholder. While this arrangement is efficient and permits the toolholder to be removed or secured to a tool support member in a short amount of time, the design of this arrangement may limit its application to toolholders having a width of one inch or greater. Since many industrial applications require the use of a cutting tool which must be mounted on a much smaller toolholder, a need exists for a quick change toolholder system for toolholders which may be designed having a width of less than one inch.
Such a system must not only have a compact design, but furthermore, provide quick connecting and disconnecting of the toolholder from the toolholder support member in an efficient manner that makes it practical for use by a machine tool operator.
The system described hereinafter is a quick change tooling system by which a toolholder is secured with a tool support member utilizing simple hardware that permits the size of the toolholder and toolholder support member to be significantly reduced over other commercially available quick change tool systems.
One embodiment of the invention is directed to an apparatus for releasably holding a toolholder with a shank having lockable surfaces and a releasable surface. The apparatus comprises a tool support member having a forwardly facing surface and a bore along a longitudinal axis, wherein the bore intersects the forwardly facing surface and extends rearwardly therefrom for receiving the shank of the toolholder. The apparatus further comprises an actuating bolt positioned within the tool support member along a radial axis R1 relative to the longitudinal axis and having a first end with a bolt locking segment having a bolt locking surface and an actuating nut rotatably fixed within the tool support member, wherein the actuating nut is threadably secured to a second end of the actuating bolt and has a nut locking segment with a nut locking surface. Rotation of the actuating bolt in a locking direction causes the actuating nut to be drawn to the bolt first end thereby drawing together the nut locking surface and the bolt locking surface to engage the toolholder lockable surfaces and to lock the toolholder within the tool support member. A second embodiment of the subject invention is directed toward a toolholder for mounting in a bore of a tool support member with a longitudinal axis and a forwardly facing surface and for being secured rearwardly along the axis within the bore by an actuating bolt with a threadably secured nut secured thereto and movable in a relative motion along an R1 axis radial to the longitudinal axis, wherein the bolt and the nut each have a locking segment with a locking surface and wherein the bolt additionally has a releasing segment with a releasing surface. The toolholder is comprised of a forward end upon which a cutting tool may be mounted and a shank adjacent to and connected to a rearwardly facing abutment face and extending rearwardly from the forward end. The shank has a releasable segment with a releasable surface engageable by the bolt releasing surface and has a pair of lockable segments with lockable surfaces defined by perforations at circumferentially spaced locations and engageable by the bolt and nut locking surfaces. Each of the lockable surfaces is urged rearwardly by one of each of the locking surfaces when the actuating bolt is rotated in a locking direction. The releasable surface is urged forwardly by the releasing surface of the actuating bolt when the actuating bolt is rotated in a releasing direction.
A third embodiment of the subject invention is directed toward a combination for mounting a toolholder into a bore in a forwardly facing surface of a tool support member. The combination is comprised of a tool support member and a toolholder. The tool support member has (i) a forwardly facing surface and a bore along a longitudinal axis, wherein the bore intersects the forwardly facing surface and extends rearwardly therefrom for receiving the shank of the toolholder, (ii) an actuating bolt positioned within the tool support member along a radial axis R1 relative to the longitudinal axis and having a first end with a bolt locking segment having a bolt locking surface, and (iii) an actuating nut rotatably fixed within the tool support member, threadably secured to a second end of the actuating bolt and having a nut locking segment having a nut locking surface. The toolholder has a forward end upon which a cutting tool may be mounted and has a shank adjacent to and connected to a rearwardly facing abutment face and extending rearwardly from the forward end. The shank has (i) a releasable segment with a releasable surface engageable by the bolt releasing surface and (ii) a pair of lockable segments with lockable surfaces defined by perforations at circumferentially spaced locations and engageable by the bolt and nut locking surfaces. Each of the lockable surfaces is urged rearwardly by one of each of the locking surfaces when the actuating bolt is rotated in a locking direction. Furthermore, the releasable surface is urged forwardly by the releasing surface of the actuating bolt when the actuating bolt is rotated in a releasing direction.